based on the technology used by japan's train. the launch of the new service expands china's high-speed railway to more than 9300 kilometers. officials plan to extend it to 16,000 kilometers by 2020. the chinese government temporarily suspended construction of high-speed train lines after 40 people died in a two-train collision last year. but it has resumed construction with the aim of helping correct economic disparities between the coastal areas and shoring up the economy. questions remain about the safety of high-speed railways. >> translator: it's good to be fast as well as safe but safety should be given priority. >> reporter: many ministry officials stress that they reinforced safety measures. these include reducing maximum speed to 303 kilometers per hour for the time being. 50 kilometers per hour slower than the trains are capable of. nhk world. >>> populous, prosperous, pushing ahead. china's wealth brought it power, wealth and problems. pollution threat continues their health and strained relations with its neighbors. fi